Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Adverse effects
RCT	40 treatment-naive people with symptoms of idiopathic writer's cramp for at least 1 year	Weakness in the hand 18/20 (90%) with botulinum A 2/19 (11%) with placebo	P value not reported
RCT	40 treatment-naive people with symptoms of idiopathic writer's cramp for at least 1 year	Pain at injection site 1/20 (5%) with botulinum A 3/19 (16%) with placebo	P value not reported